THURSDAY, April 28, 2022 (HealthDay News) -- COVID-19 death rates are significantly higher in U.S. counties that remain largely unvaccinated than in those where more people have gotten their shots, according to a new study.
The findings add to evidence that vaccination among individuals can prevent infection and illness on a much larger scale, University of Oxford professor Christopher Dye wrote in an editorial accompanying the study.
"The findings of this study also make clear that many more lives could have been saved, and will be saved, by encouraging people to keep up to date with vaccination in the face of waning immunity and new coronavirus variants and by achieving even higher population coverage," Dye explained. "How many lives is a matter for others to explore. Meanwhile, this new study is another confidence booster for COVID-19 vaccines."
For the study, researchers at the U.S. Centers for Disease Control and Prevention analyzed data on more than 30 million COVID-19 cases and more than 400,000 COVID deaths reported in 2,558 counties in 48 states between December 2020 and December 2021.
The counties were classified as having very low (0 to 9%), low (10 to 39%), medium (40 to 69%), or high (70% or more) vaccination rates — defined as the percentage of adults who had gotten at least one dose of a COVID-19 vaccine.
After accounting for other factors, the researchers determined that higher vaccination rates were associated with lower levels of COVID-19 cases and deaths.
When the Alpha variant was dominant in the United States early last year, COVID-19 death rates were 60%, 75% and 81% lower in counties with low, medium and high vaccination coverage, respectively, than in counties with very low coverage, the study team reported.
Meanwhile, infection rates were 57%, 70% and 80% lower in low, medium and high vaccination counties, respectively, than in those with very low coverage, the investigators found.
Similar declines in deaths were also seen during the second half of 2021 when the Delta variant became dominant in the United States, with smaller drops in cases, according to the report published April 27 in the BMJ.
Amitabh Bipin Suthar, a senior epidemiologist for Coronavirus Disease Response at the CDC, led the study.
As of April 11, 2022, more than 11 billion COVID-19 vaccine doses had been administered worldwide. The World Health Organization's goal is to vaccinate 70% of the world's population by the middle of this year.
More information
There's more on COVID-19 vaccines at the U.S. Centers for Disease Control and Prevention.
SOURCE: BMJ, news release, April 27, 2022